Starting Gate: Veep On Guessing

Mitt Romney joined John McCain yesterday for a campaign swing through two of Romney's primary strongholds and renewed speculation about the possibility of a joint ticket for the fall. Sure, the two were bitter rivals just a month ago but this is politics and since suspending his presidential campaign, Romney has even gone so far as to say it would be an "honor" to be on the ticket.

Of course there was more than an audition happening on the trip. Romney's strong ties in Utah and Colorado are sure to provide some cash infusion into McCain's campaign, something the presumptive nominee can't get enough of at the moment.

Meanwhile, Michael Bloomberg's introduction of Barack Obama for his economic speech yesterday sparked speculation that the New York City Mayor might be more than just a potential high-profile endorsement for the Democratic front-runner. Bloomberg says his support is up for grabs but he has flirted openly with Obama now on two very public occasions. With the perception that Obama has problems within the Jewish community, would it not be an interesting pairing?

Yes, the guessing game over vice presidential selections has begun – even before the Democratic primary is settled. There seems to be some expectations among Democrats for an Obama-Clinton ticket, or the other way around. A recent Pew poll showed that 66 percent of Clinton supporters want her to pick Obama for the ticket should she end up with the nomination while a smaller number, 59 percent, of Obama supporters said the same of Clinton.

The guessing game is about to begin in earnest but keep in mind that about three quarters of all the names you hear tossed out will be just that – a game. And everyone wants in. For governors, senators and other esteemed figures, nothing is quite so gratifying as having ones name attached to the words "short list," or even "potential vice presidential nominee." Everywhere these candidates travel over the next few weeks and months, there will be at least one "potential" running mate there to greet them – and get a mention.

The reality is that far fewer names will end up on that short list than will be mentioned for it in press accounts. The first rule of selection a running mate is "do no harm." Avoiding an "Eagleton moment" is of paramount importance. Only then will other considerations come into play – where can the running mate help -- in a state, with a demographic group or to fill a gap in the nominee's resume. Would Obama need some "experience" on the ticket? Would Clinton need a fresh face? Does McCain need youth?

Those conversations could soon become a dominant part of the political discussion and endless speculation over politicians with little to back it up. Have you been mentioned yet?

Pennsylvania Boost For Obama: Hillary Clinton has locked up most of the Pennsylvania establishment, from Gov. Ed Rendell to the mayors of both Philadelphia and Pittsburgh. But Obama will receive the endorsement of Sen. Bob Casey Jr. this morning, a potential boost to his campaign by helping him attract some of the state's so-called Casey Democrats. Named after Casey's late father, these are blue-collar, white, Catholics who appear tailor-made for Clinton's campaign. As governor of Pennsylvania, Bob Casey Sr. made waves in 1992 when he skipped the Democratic National Convention because he was refused a speaking slot due to his pro-life views.

Introducing John McCain: You might think you know John McCain pretty well by now but his campaign wants to make sure that he's re-introduced to voters the way they want him to be. McCain next week will embark upon a "Service to America" tour where he will, according to the campaign, "introduce himself to the nation through a series of speeches and visits that trace the life of a man indebted to his nation, humbled by the opportunity to serve his country, honored by his family's love and deeply moved by his fellow Americans' courage and sacrifice."

To that end, the campaign is releasing a new ad today, billed as the first ad of the general election featuring footage of McCain as a prisoner of war. The ad will begin running in New Mexico. Partial text: "What must a president believe about us? About America? That she is worth protecting ... that liberty is priceless ... our people, honorable ... our future, prosperous, remarkable and free. And, what must we believe about that president? What does he think? Where has he been? Has he walked the walk?" Check back at Horserace later today for the video of the ad and more on McCain's tour.

Around The Track

DNC Chair Howard Dean wants this nomination wrapped up by July, 1st he told CBS News's "The Early Show" this morning. "I think the superdelegates have already been weighing in. I think that there's 800 of them and 450 of them have already said who they're for. I'd like the other 350 to say who they're at some point between now and the first of July so we don't have to take this into the convention," he said. Dean is also taking Democrats to task for their increasingly bitter debate, calling on them to cool it. "You do not want to demoralize the base of the Democratic Party by having the Democrats attack each other," Dean told the AP. "Let the media and the Republicans and the talking heads on cable television attack and carry on, fulminate at the mouth. The supporters should keep their mouths shut about this stuff on both sides because that is harmful to the potential victory of a Democrat."

Obama has a new ad up in Indiana, featuring the candidate talking about jobs dressed in a casual leather jacket. See the video here.

A legal review by McCain backer Ted Olson and Obama supporter Lawrence Tribe concludes that McCain is Constitutionally eligible to be president. "Based on the original meaning of the Constitution, the Framers' intentions, and subsequent legal and historical precedent, Senator McCain's birth to parents who were U.S. citizens, serving on a U.S. military base in the Panama Canal Zone in 1936, makes him a 'natural born citizen' within the meaning of the Constitution,"They found.